1 Answer
1

Well, they will all work but they will give different results - not exactly sure what result you are looking for.
I would however guess that you would get the result you want using query 2 and 3 as you have have used () to "group" the Or statements together.
If you don't do that you will end up "linking" the last OR with the following AND.
Also instead of having a number of OR statement you could consider using the IN operator.

Select * from TABLE
where vendor In ("vendor1", "vendor2")
AND site_status In ("status1", "status2")
into sel